constraints
~~~~~~~~~~~

**type**: array or :class:`Symfony\\Component\\Validator\\Constraint` **default**: ``null``

Allows you to attach one or more validation constraints to a specific field.
For more information, see :ref:`Adding Validation<form-option-constraints>`.
This option is added in the :class:`Symfony\\Component\\Form\\Extension\\Validator\\Type\\FormTypeValidatorExtension`
form extension.
